No drain, autologous transfusion drain or suction drain? A randomised prospective study in total hip replacement surgery of 168 patients

We performed a prospective, randomised controlled trial to assess the differences in the use of a conventional suction drain, an Autologous Blood Transfusion (ABT) drain and no drain, in 168 patients. There was no significant difference between the drainage from ABT drains ( mean : 345 ml) and the suction drain (314 ml). Forty percent of patients receiving a suction drain had a haemoglobin level less than 10 g/dL at 24 hours, compared to 35% with no drain and 28% with an ABT drain. Patients that had no drains had wounds that were dry significantly sooner, mean 3.0 days compared to a mean of 3.9 days with an ABT drain and a mean of 4 days with a suction drain. Patients that did not have a drain inserted stayed in hospital a significantly shorter period of time, compared with drains. We feel the benefits of quicker drying wounds, shorter hospital stays and the economic savings justify the conclusion that no drain is required after hip replacement

La zoomification de l’enseignement médical : les solutions virtuelles précipitées lors de la COVID-19 peuvent-elles nous préparer pour une prochaine perturbation dans l’enseignement? Revue exploratoire

Introduction: In response to the COVID-19 pandemic, educators have increasingly shifted delivery of medical education to online/distance learning. Given the rapid and heterogeneous nature of adaptations; it is unclear what interventions have been developed, which strategies and technologies have been leveraged, or, more importantly, the rationales given for designs. Capturing the content and skills that were shifted to online, the type of platforms used for the adaptations, as well as the pedagogies, theories, or conceptual frameworks used to inform the adapted educational deliveries can bolster continued improvement and sustainability of distance/online education while preparing medical education for future large-scale disruptions. Methods: We conducted a scoping review to map the rapid medical educational interventions that have been adapted or transitioned to online between December 2019 and August 2020. We searched MEDLINE, EMBASE, Education Source, CINAHL, and Web of Science for articles pertaining to COVID-19, online (distance) learning, and education for medical students, residents, and staff. We included primary research articles and reports describing adaptations of previous educational content to online learning. Results: From an initial 980 articles, we identified 208 studies for full-text screening and 100 articles for data extraction. The majority of the reported scholarship came from Western Countries and was published in clinical science journals. Cognitive content was the main type of content adapted (over psychomotor, or affective). More than half of the articles used a video-conferencing software as the platform to pivot their educational intervention into virtual. Unfortunately, most of the reported work did not disclose their rationale for choosing a platform. Of those that did, the majority chose technological solutions based on availability within their institutions. Similarly, most of the articles did not report the use of any pedagogy, theory, or framework to inform the educational adaptations.Introduction : En réponse à la pandémie de la COVID-19, l’enseignement médical a été progressivement déplacé vers l’espace virtuel. Compte tenu de la rapidité et de l’hétérogénéité des adaptations opérées, nous n’avons qu’une idée peu précise des activités éducatives élaborées, des stratégies et des technologies mobilisées et, plus important encore, des raisons avancées pour les motiver. Une meilleure connaissance du contenu et des compétences dont l’enseignement a été transféré en ligne, du type de plateformes utilisées pour le virage, ainsi que des pédagogies, des théories ou des cadres conceptuels utilisés pour guider les activités éducatives adaptées soutiendrait une amélioration continue et la pérennité de l’enseignement à distance, tout en préparant la formation médicale à de futures perturbations d’envergure. Méthodes : Nous avons effectué une revue exploratoire pour recenser les activités éducatives en médecine qui ont été expéditivement adaptées ou transposées en ligne entre décembre 2019 et août 2020. Nous avons interrogé les bases de données MEDLINE, EMBASE, Education Source, CINAHL et Web of Science à la recherche d’articles portant sur la COVID-19, sur l’apprentissage en ligne (à distance) et sur la formation des étudiants en médecine, des résidents et du personnel enseignant. Nous avons inclus des articles de recherche originale et d’autres décrivant l’adaptation de contenus éducatifs à l’apprentissage en ligne. Résultats : Des 980 articles trouvés, nous avons sélectionné 208 études pour un examen du texte intégral et 100 articles pour une extraction de données. La plupart des travaux provenaient de pays occidentaux et ont été publiés dans des revues médicales. Le type de contenu adapté était principalement cognitif, dans une moindre mesure psychomoteur ou affectif. Plus de la moitié des articles présentaient un logiciel de visioconférence comme plateforme utilisée pour transposer des activités éducatives en mode virtuel. Malheureusement, la plupart des études ne précisaient pas les raisons justifiant le choix de plateforme. Celles qui l’ont fait indiquaient majoritairement que les solutions technologiques avaient été choisies en fonction de leur disponibilité au sein de l’établissement. De la même manière, seulement une poignée d’articles font état de l’utilisation d’une pédagogie, d’une théorie ou d’un cadre pour guider les adaptations pédagogiques

Refined Phenotyping of Modic Changes: Imaging biomarkers of prolonged severe low back pain and disability

Imaging biomarkers of prolonged severe low back pain and disablitypublished_or_final_versio

Charge asymmetries of top quarks at hadron colliders revisited

A sizeable difference in the differential production cross section of top- compared to antitop-quark production, denoted charge asymmetry, has been observed at the Tevatron. The experimental results seem to exceed the theory predictions based on the Standard Model by a significant amount and have triggered a large number of suggestions for "new physics". In the present paper the Standard Model predictions for Tevatron and LHC experiments are revisited. This includes a reanalysis of electromagnetic as well as weak corrections, leading to a shift of the asymmetry by roughly a factor 1.1 when compared to the results of the first papers on this subject. The impact of cuts on the transverse momentum of the top-antitop system is studied. Restricting the ttbar system to a transverse momentum less than 20 GeV leads to an enhancement of the asymmetries by factors between 1.3 and 1.5, indicating the importance of an improved understanding of the $t\bar t$-momentum distribution. Predictions for similar measurements at the LHC are presented, demonstrating the sensitivity of the large rapidity region both to the Standard Model contribution and effects from "new physics".Comment: 23 pages. Final version to appear in JHE

The theory of international business: the role of economic models

This paper reviews the scope for economic modelling in international business studies. It argues for multi-level theory based on classic internalisation theory. It present a systems approach that encompasses both firm-level and industry-level analysis

Mutational analysis of the Ve1 immune receptor that mediates Verticillium resistance in tomato

Pathogenic Verticillium species are economically important plant pathogens that cause vascular wilt diseases in hundreds of plant species. The Ve1 gene of tomato confers resistance against race 1 strains of Verticillium dahliae and V. albo-atrum. Ve1 encodes an extracellular leucine-rich repeat (eLRR) receptor-like protein (RLP) that serves as a cell surface receptor for recognition of the recently identified secreted Verticillium effector Ave1. To investigate recognition of Ave1 by Ve1, alanine scanning was performed on the solvent exposed ß-strand/ß-turn residues across the eLRR domain of Ve1. In addition, alanine scanning was also employed to functionally characterize motifs that putatively mediate protein-protein interactions and endocytosis in the transmembrane domain and the cytoplasmic tail of the Ve1 protein. Functionality of the mutant proteins was assessed by screening for the occurrence of a hypersensitive response upon co-expression with Ave1 upon Agrobacterium tumefaciens-mediated transient expression (agroinfiltration). In order to confirm the agroinfiltration results, constructs encoding Ve1 mutants were transformed into Arabidopsis and the transgenes were challenged with race 1 Verticillium. Our analyses identified several regions of the Ve1 protein that are required for functionality

Paclitaxel induces immunogenic cell death in ovarian cancer via TLR4/IKK2/SNARE-dependent exocytosis

Emerging evidence shows that the efficacy of chemotherapeutic drugs are reliant on their capability to induce immunogenic cell death (ICD), thus transforming dying tumor cells into antitumor vaccines. We wanted to uncover potential therapeutic strategies that target ovarian cancer by having a better understanding of the standard-of-care chemotherapy treatment. Here, we showed in ovarian cancer that paclitaxel induced ICD-associated DAMPs (i.e. damage-associated molecular patterns, such as CALR exposure, ATP secretion and HMGB1 release) in vitro and elicited significant antitumor responses in tumor vaccination assays in vivo. Paclitaxel-induced TLR4 signaling was essential to the release of DAMPs, which lead to the activation of NF-κB-mediated CCL2 transcription and IKK2-mediated SNARE-dependent vesicle exocytosis, thus exposing CALR on the cell surface. Paclitaxel induced ER stress, which triggered PERK activation and eIF2α phosphorylation independent of TLR4. Paclitaxel chemotherapy induced T cell infiltration in ovarian tumors of the responsive patients; CALR expression in primary ovarian tumors also correlated with patients' survival and patient response to chemotherapy. These findings suggest that the effectiveness of paclitaxel relied upon the activation of antitumor immunity through ICD via TLR4 and highlighted the importance of CALR expression in cancer cells as an indicator of response to paclitaxel chemotherapy in ovarian cancer

Chiral U(1) flavor models and flavored Higgs doublets: the top FB asymmetry and the Wjj

We present U(1) flavor models for leptophobic Z' with flavor dependent couplings to the right-handed up-type quarks in the Standard Model, which can accommodate the recent data on the top forward-backward (FB) asymmetry and the dijet resonance associated with a W boson reported by CDF Collaboration. Such flavor-dependent leptophobic charge assignments generally require extra chiral fermions for anomaly cancellation. Also the chiral nature of U(1)' flavor symmetry calls for new U(1)'-charged Higgs doublets in order for the SM fermions to have realistic renormalizable Yukawa couplings. The stringent constraints from the top FB asymmetry at the Tevatron and the same sign top pair production at the LHC can be evaded due to contributions of the extra Higgs doublets. We also show that the extension could realize cold dark matter candidates.Comment: 40 pages, 10 figures, added 1 figure and extended discussion, accepted for publication in JHE

On-shell Recursion in String Theory

We prove that all open string theory disc amplitudes in a flat background obey Britto-Cachazo-Feng-Witten (BCFW) on-shell recursion relations, up to a possible reality condition on a kinematic invariant. Arguments that the same holds for tree level closed string amplitudes are given as well. Non-adjacent BCFW-shifts are related to adjacent shifts through monodromy relations for which we provide a novel CFT based derivation. All possible recursion relations are related by old-fashioned string duality. The field theory limit of the analysis for amplitudes involving gluons is explicitly shown to be smooth for both the bosonic string as well as the superstring. In addition to a proof a less rigorous but more powerful argument based on the underlying CFT is presented which suggests that the technique may extend to a much more general setting in string theory. This is illustrated by a discussion of the open string in a constant B-field background and the closed string on the level of the sphere.Comment: 36 + 9 pages text, one figure, v3: added discussion on relation to old-fashioned factorization, typos corrected, published versio

Overcoming obstacles associated with other learning experiences and school-based assessment: Perspectives of high school students with visual impairment in Hong Kong - Collaborative research project report

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